Catalysts
·
2018
·Vol. 8
·期 12
·642
·
IF 3.465
Yan Gao,Tao Luan,Mingyang Zhang,Wenke Zhang,Wenchen Feng
A series of Mn−Fe−Ce−Ox/γ-Al2O3nanocatalysts were synthesized with different Mn/Fe ratios for the catalytic oxidation of NO into NO2and the catalytic elimination of NOxvia fast selective catalytic reduction (SCR) reaction. The effects of Mn/Fe ratio on the physicochemical properties of the samples were analyzed by means of various techniques including N2adsorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), H2-temperature-programmed reduction (TPR), NH3-temperature-programmed desorption (TPD) and NO-TPD, meanwhile, their catalytic performance was also evaluated and compared. Multiple characterizations revealed that the catalytic performance was highly dependent on the phase composition. The Mn15Fe15−Ce/Al sample with the Mn/Fe molar ratio of 1.0 presented the optimal structure characteristic among all tested samples, with the largest surface area, increased active components distributions, the reduced crystallinity and diminished particle sizes. In the meantime, the ratios of Mn4+/Mnn+, Fe2+/Fen+and Ce3+/Cen+in Mn15Fe15−Ce/Al samples were improved, which could enhance the redox capacity and increase the quantity of chemisorbed oxygen and oxygen vacancy, thus facilitating NO oxidation into NO2and eventually promoting the fast SCR reaction. In accord with the structure results, the Mn15Fe15−Ce/Al sample exhibited the highest NO oxidation rate of 64.2% at 350 °C and the broadest temperature window of 75–350 °C with the NOxconversion >90%. Based on the structure–activity relationship discussion, the catalytic mechanism over the Mn−Fe−Ce ternary components supported byγ-Al2O3were proposed. Overall, it was believed that the optimization of Mn/Fe ratio in Mn−Fe−Ce/Al nanocatalyst was an extremely effective method to improve the structure–activity relationships for NO pre-oxidation and the fast SCR reaction.
✓ 已验证
DOI
高影响因子
ADVANCED ENGINEERING MATERIALS
·
2025
·Vol. 28
·期 2
·e202501970
·
IF 3.3
Zhishuai Liu,Siran Wang,Yujia Liu,Junwei Sha,Rui Li,Xudong Yang
Achieving the stability of pore structure and the enhancement of mechanical properties is the prominent target for aluminum (Al) foam design. In this work, the effects of manganese (Mn) content on the pore structure, mechanical properties, and deformation behavior of Al Mn foams are investigated. The results show that the appropriate addition of Mn (1.5 wt%) achieves a remarkable balance between energy absorption capacity (4.37 MJ m −3 ) and pore uniformity (standard deviation of 0.95 mm in average pore size), representing substantial enhancements of 193.28% in yield strength and 385.56% in energy absorption capacity compared to pure Al foams. These enhancements are attributed to a refined pore architecture, finely dispersed Al 6 Mn precipitates, and a sequential collapse mechanism, which collectively enable progressive energy dissipation. The application of the entropy weight method is pioneered in this study to establish a predictive framework for multiobjective design, demonstrating that energy absorption and pore uniformity are crucial factors for the matrix design of Al foams. These findings offer a potential strategy for future engineering applications of metal foam design.
✓ 已验证
DOI
高影响因子
Molecular Catalysis
·
2018
·
IF 0
Gui Liu,Lei Sun,Wei Luo,Yue Yang,Junhua Liu,Fang Wang,Curtis J. Guild
Aerobic Baeyer-Villiger oxidation of ketones into corresponding esters were performed over mesoporous Mn-Ce and Mn-Co composite oxides prepared by co-impregnation method and benzaldehyde was used as the sacrificing agent. It was found that the best conversion and selectivity were obtained when the Mn/Ce mole ratio was 1:2 (denoted as Mn 0.33 Ce 0.67 O s ) through investigating the effect of Mn/Ce mole ratio on the catalytic activity. Interestingly, Mn 0.33 Co 0.67 O s (Mn/Co mole ratio was 1:2) catalyst had no catalytic activity for this reaction. X-ray diffraction (XRD) results showed that MnO x was completely dissolved into the CeO 2 lattice, and Mn 0.33 Co 0.67 O s sample was existed in the form of spinel structure (Co, Mn) (Mn, Co) 2 O 4 and obvious peaks of Co 3 O 4 . Nitrogen adsorption-desorption measurements revealed that Mn 0.67 Ce 0.33 O s , Mn 0.5 Ce 0.5 O s , Mn 0.33 Ce 0.67 O s and Mn 0.33 Co 0.67 O s materials possessed mesoporous structure. X-ray photoelectron spectroscopy (XPS) analysis showed that the highest concentration of Ce 3+ on the surface of Mn 0.33 Ce 0.67 O s catalyst, which could create unsaturated chemical bonds, charge imbalance, and oxygen vacancies on the surface of samples, it is beneficial to the oxidation reaction. Additionally, XPS data revealed that Mn 0.33 Ce 0.67 O s catalyst has great potential in catalytic oxidation due to the large amount of active oxygen species on the surface. In addition, manganese and cobalt species on the surface of Mn 0.33 Co 0.67 O s are almost present in the form of Mn 2+ and Co 3+ , it is known that Mn 2+ can serve as a potent antioxidant and scavenge the activity of active oxygen species, while Co 3+ ions can prevent the formation of oxygen vacancies and inhibit the release of reactive oxygen species, thus the presence of Mn 2+ and Co 3+ inhibited the catalytic activity of Mn 0.33 Co 0.67 O s catalyst. The diffuse reflectance ultraviolet-visible spectroscopy (DR-UV-vis) and hydrogen temperature-programmed reduction (H 2 -TPR) results are in accordance XPS data.
✓ 已验证
产品关联
DOI
Food Analytical Methods
·
2013
·Vol. 7
·期 2
·291-297
·
IF 1.969
Wen Shengping,Zhu Xiashi
A simple and rapid method based on dispersive liquid–liquid microextraction with room temperature ionic liquid 1,3-dibutylimidazolium hexafluorophosophate ([BBIM][PF 6 ]) coupled to flame atomic absorption spectrometry was developed for the speciation of Mn(II)/Mn(VII) in tea samples. The main factors affecting dispersive liquid–liquid microextraction were investigated in detail. Mn(II) and total manganese [Mn(II)+Mn(VII)] were quantitatively extracted after adjusting aqueous sample solution to pH 10.0 and 7.0, respectively. Mn(VII) was calculated by subtraction of Mn(II) from total manganese. Under the optimized conditions, the limits of detection (3 σ ) for Mn(II) and Mn(VII) were 0.26 and 1.86 ng/mL, and their relative standard deviations were 2.6 and 4.8 % ( n = 7, c = 25.00 ng/mL). The proposed method was validated by the determination of Mn(II) and Mn(VII) in the certified reference material [GBW(E)08513] of tea sample and different local tea samples with satisfactory results.
✓ 已验证
产品关联
DOI
高影响因子
ARCHIVES OF MICROBIOLOGY
·
2022
·Vol. 204
·期 3
·1-14
·
IF 2.667
Chen Sha,Ding Zhexu,Chen Jinyuan,Luo Jun,Ruan Xiaofang,Li Zongpei,Liao Fengfeng,He Jing,Li Ding
Bacterial non-enzymatic Mn(II) oxidation involving reactive oxygen species (ROS) (i.e., indirect oxidation), initially discovered from a marine alpha-proteobacterium, is believed to be of importance in controlling biogeochemical cycles. For soil-borne bacteria, however, evidence of indirect Mn(II) oxidation remains unclear. In this study, the indirect Mn(II) oxidation was evidenced in a soil-borne bacterium, Providencia sp. LLDRA6. First, with and without 50 mM of Mn(II) exposure for LLDRA6, 300 differentially expressed genes were found to be linked to Mn(II) exposure via transcriptome sequencing. Among them, an operon, responsible for phenylacetic acid catabolism, was sharply upregulated in transcription, drawing us a special attention, since its transcriptional upregulation has recently shown to be important for withstanding ROS. Next, a fluorometric probe, 2′,7′-Dichlorofluorescin diacetate (DCFDA), was used to qualitatively detect ROS from cells, showing a distinct increase in fluorescence intensities of ROS during Mn(II) exposure. Furthermore, concentrations of superoxide and hydrogen peroxide from cells were detected, respectively, with and without Mn(II) exposure, exhibiting that when Mn(II) oxidation occurred, superoxide concentration significantly increased but hydrogen peroxide concentration significantly decreased. Particularly, superoxide produced by LLDRA6 was proven to be the oxidant for Mn(II) in the formation of Mn oxides. Finally, we predicted links between phenylacetic acid metabolism pathway and ROS during Mn(II) exposure, proposing that the excessive ROS, generated in response to Mn(II) exposure, transcriptionally activate phenylacetic acid catabolism presumably by increasing concentrations of highly reactive oxepins.
✓ 已验证
DOI
PubMed
高影响因子
ELECTROCHIMICA ACTA
·
2019
·
IF 5.383
Aijia Wei,Wen Li,Qian Chang,Xue Bai,Rui He,Lihui Zhang,Zhenfa Liu,Yanji Wang
Mg 2+ /F − co-doped LiNi 0.5 Mn 1.5 O 4 cathode material was synthesized by a facile one-step solid-state process. The effect of Mg 2+ /F − co-doping on grain morphology, phase structure, and electrochemical properties was studied by a series of characterizations. Scanning-electron-microscopy images show that Mg 2+ /F − co-doped LiNi 0.5 Mn 1.5 O 4 (denoted LNMO-MF) particles grow larger than pure LiNi 0.5 Mn 1.5 O 4 particles. X-ray diffraction, Raman spectra , Fourier transformation infrared spectroscopy , X-ray photoelectron spectroscopy, and cyclic-voltammetry tests indicate that all samples mainly display a Fd -3m space group and more Mn 3+ ions in the LNMO-MF sample after Mg 2+ /F − co-doping, which is conducive to increasing the cationic disorder degree and enhancing the electronic conductivity of electrode material. Results show that the LNMO-MF cathode material delivers an excellent rate performance with discharge capacities of 142, 144, 140 136, 132, 124, 115, and 100 mAh g −1 at 0.2, 0.5, 1, 2, 3, 5, 7, and 10C (1C = 140 mAh g −1 ), respectively. Remarkably, LNMO-MF also shows cycling stability with a capacity retention of 86.2% at 5C after 400 cycles, which is much higher than that of pure LiNi 0.5 Mn 1.5 O 4 (67.7%). The improvement of LNMO-MF's electrochemical properties could be ascribed to the Mg 2+ /F − co-doping, delivering a more stable structure, better crystallinity , the highest Li + diffusion coefficient , and the lowest charge-transfer resistance.
研究领域:
材料科学
·
电化学
·
无机非金属材料
·
能源存储
·
锂离子电池
·
固态化学
·
功能材料
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY COMMUNICATIONS
·
2026
·
IF 5.9
Tianchi Zhang,Yaoting Wen,Chenglong Xia,Xuhui Xu,Guoping Wang,Yongcai Zhang
Developing efficient, recyclable heterogeneous catalysts for the oxidation of p-methoxytoluene (p-MT) remains a critical challenge in industrial organic synthesis. Herein, a ternary Co-Mn-Ce oxide catalyst was synthesized via co-precipitation and systematically optimized to address limitations in mass transfer and catalyst reusability. By modulating the Ce content, the structural evolution from cobalt‑manganese spinel phases to CeO 2 -dominated crystallites was demonstrated, significantly influencing catalytic performance. The CoMn 3 Ce 1.9 catalyst with high Ce loading exhibited a p-MT conversion of 95.0% under mild conditions, outperforming the low-Ce analogs, which showed only 50–60% p-MT conversion. Characterization revealed that CeO 2 -rich catalysts featured larger average pore sizes (18 nm vs. 2–4 nm for spinel-dominated systems), mitigating diffusion constraints and enhancing oxygen activation. High-concentration experiments (8 mL p-MT) maintained 77.7% conversion after 12 h, but with increased esterification to p-methoxybenzyl acetate (p-MBAc). Remarkably, the catalyst retained >70% activity over four runs. This work highlights the optimized pore architecture in overcoming traditional limitations of spinel-based catalysts, offering a sustainable, scalable strategy for aromatic aldehyde synthesis. The findings provide critical insights into designing multifunctional heterogeneous catalysts for selective C(sp 3 )-H bond activation, with broad implications for green chemical manufacturing.
✓ 已验证
DOI
高影响因子
Advanced Materials Technologies
·
2026
·
IF 6.2
Peng Zhang,Hongyan Sun,Wei Zhang,Jiaying Zhang,Bo Chen,Adil Farooq Lodhi,Chan Li,Zijin Zeng,Chutian Wang,Yuguo Dai,Jiapeng Yang,Yinyan Wang,Tao Jiang,Lin Feng
Recent studies highlight piezocatalytic therapy (PCT) as a superior curative strategy owing to its stable dynamic control compared to sonoluminescence-activated sonodynamic therapy (SDT). However, most nano-piezoelectric catalysts' catalytic efficiency in biosafety and biocompatibility is unsatisfactory. Herein, this study modifies the typical piezoelectric material tetragonal barium titanate (T-BTO). It introduces novel manganese (Mn) -coated T-BTO nanoparticles (MCTB) that possess magnetic resonance imaging (MRI) ability and enhanced PCT effects. The encapsulation of Mn masks the piezoelectric effect of the nanoparticles, and the acidic tumor microenvironment (TME) triggers the stripping of Mn and restoration of the piezoelectric effect of T-BTO, which produces ROS under ultrasonic irradiation. The presence of Mn ions also enhances the MRI property of the tumor site as a contrast agent. Additionally, ultrasonic irradiation promotes the conversion of low-valence Mn into a high-valence state, further stimulating ROS production. The biosafety, therapeutic effects, T1-weighted MRI, and piezoresponse of MCTB are investigated in vitro. Animal studies also indicate that the nanoparticles display good treatment performance when activated by ultrasound and guided by MRI. Therefore, this study develops an MCTB particle that boosts ROS generation, enables tumor-specific ROS release, and enhances T1-weighted MRI, offering a safe PCT approach for tumors.
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2026
·
IF 9
Bo Song,Zhenxing Shen,Zitong Wang,Qin Peng,Jia Liu
Traditional Mn-based NH 3 -SCR catalysts have a narrow temperature window, limiting low-temperature use. In this work, Mn@N-7 was prepared by a simple hydrothermal method using potassium permanganate and urea. The hydrothermal conditions are much milder than those used for most Mn-based catalysts. Graphite felt (GF) serves as a green support, providing a 3D carbon fiber network for uniform growth of manganese oxide nanowebs. Its high surface area (83.10 m 2 g −1 ) and open channels promote active species dispersion and fast mass transfer. The strong carbon framework prevents sintering at high temperatures. Mn@N-7 shows nearly 100% NO conversion at 100–200 °C and maintains good activity for 30 h. Its estimated cost is 1.2–1.8 USD kg −1 , lower than 3.0–4.5 USD kg −1 for V 2 O 5 -WO 3 /TiO 2 catalysts. The mild hydrothermal process avoids high-temperature calcination. This work demonstrates GF is a sustainable support and offers guidance for carbon-based catalysts in clean air applications.
✓ 已验证
产品关联
DOI
高影响因子
LANGMUIR
·
2022
·
IF 4.331
Chenming Han,Xiaoyan Yuan,Lixia Ren
A magnetic surfactant, which combines the properties of a surfactant with magnetic responsiveness, shows great potential in biotechnology, separation, adsorption, and catalysis, especially in non-invasive manipulation through a magnetic field. However, a molecularly magnetic surfactant is usually paramagnetic for the amorphous and less ordered structures. In this work, magnetic surfactant 1-methyl-3-hexadecane-imidazolium [MnCl2Br] (C16M[Mn]) is reported to self-assemble in water. The C16M[Mn] magnetic surfactant self-assembles in water to form a lamellar hydrogel from 10 to 50 wt % at and below room temperature. The hydrogel changes from a gel to a sol at 30 °C, and the hexadecane chains in the hydrogel change from noncrystalline to crystalline at 0 °C. In the hydrogel state, the lamellar domain spacing is varied from 36 to 45 nm depending on the concentration and self-assembly temperature. After self-assembly, the magnetic susceptibility of the freeze-dried magnetic surfactant is increased. Most important is the fact that the freeze-dried sample at a high concentration (40–50 wt %) shows the highest magnetic susceptibility, which is related to the closer molecular packing and the more ordered structures. The self-assembly-induced increase in magnetic susceptibility provides a method for improving the magnetic properties of a magnetic surfactant.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2022
·Vol. 33
·期 19
·15520-15532
·
IF 2.779
Zhang Xiaoyan,Yang Xu,Wang Zhaopeng,Pan Qi,Chu Baojin,Zuo Ruzhong
Our previous work proposed that except for ferromagnetic and piezoelectric properties, mechanical quality factor is also an important parameter for high magnetoelectric response of BiFeO 3 -based multiferroic ceramics. In this work, in order to improve the mechanical quality factor of BiFeO 3 -based ceramics and obtain higher magnetoelectric response, we use Mn as a dopant and prepare 0.75BiFe 1− x Mn x O 3 -0.25BaTiO 3 ( x = 0, 0.0025, 0.005, 0.0075, 0.01) ceramics. The dielectric, piezoelectric, magnetic, and magnetoelectric properties of the ceramics with different Mn doping levels and different sintering temperatures are studied comprehensively. We find that the piezoelectric response, mechanical quality factor, ferromagnetic property, and magnetoelectric response can be improved by optimization of the composition and sintering temperature of the ceramics. A large magnetoelectric coefficient α E \(\sim\) 2 V/(cm Oe) is achieved at resonant frequency when doping content of Mn is 0.75 mol% and sintering temperature is 1030 \(\mathrm{^\circ{\rm C} }\) . Such high value of α E is attributed to the combined effect of improved mechanical quality factor, high piezoelectric coefficient, and enhanced ferromagnetism. It is among the largest α E values obtained in single-phase BiFeO 3 -based ceramics. Moreover, our work further verifies the mechanical quality factor is an important parameter to achieve a high magnetoelectric response in BiFeO 3 -based ceramics.
✓ 已验证
产品关联
DOI
高影响因子
Nano Research
·
2023
·
IF 9.9
Rong Qian,Yuwen Chao,Liu Yingkai,Liu Yuanrong,Wang Chunyang,Wang Yang,Zhang Ding,Wen Zhen
Developing highly robust and efficient electrode materials is of critical importance to promoting the energy density of current supercapacitors for commercialization. Herein, we report an efficient catalyst with monodispersed Mn single-atoms embedded in carbon nanotubes (Mn-CNTs) for enhancing the electrode performance of supercapacitors. A high specific capacitance (1523.6 F·g −1 at 1.0 A·g −1 ) can be achieved, which is about twice as high as the specific capacitance of the electrode material without the introduction of Mn single-atoms. Remarkably, the asymmetric electrochemical capacitor created with Mn-CNT and activated carbon exhibits a high energy density of 180.8 Wh·kg −1 at a power density of 1.4 kW·kg −1 , much higher than most reported results. The study shows that the integration of Mn atoms into the CNT can enhance the charge transport capacity and the number of polar active sites of Mn-CNT and then facilitate chemical interactions between Mn-CNT and OH − . This work provides a novel strategy to enable high-energy storage in supercapacitors by introducing single-atoms into carbon nanotubes to improve electrodes’ energy density and cycle life.
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）